With swift advance of economy, significant increase of population and rapid development of industry and agriculture, industrial wastewater, agricultural wastewater and domestic wastewater are gradually increasing day by day. Currently, a large amount of agricultural wastewater, industrial wastewater, agricultural wastewater and domestic wastewater is directly discharged into rivers, lakes, oceans and other water bodies without any treatment; accordingly, these water bodies include various pollutants with complicated compositions, which seriously damages the ecological balance of these water bodies, and then results in various environmental, economic and social losses.
For the purpose of solving the problem that the water bodies are currently seriously polluted, environmental workers have been actively searching solutions. The first kind of current available treatment method is to reduce pollution sources so as to control point source pollution and diffused pollution; however, the method only depends on the self-purification ability of the water bodies, and the water bodies need a lot of time to recover. The second kind of current available treatment method is to establish a large ecological park, which can clean pollutants by water plants; however, the method needs a lot of land area, which limits its application range; besides, the water bodies of the method are of low flow speed, as the method needs more time to purify water. The third kind of current available treatment method is to clean the mud at the bottoms of the water bodies and re-inject water into the water bodies, which can remove the mud including pollutants to clean the inner sources polluting the water bodies, and provide water with better quality to increase the self-purification ability and environment capacity of the water bodies. However, the above methods can just temporarily purify the water bodies, but cannot permanently solve the pollution problem; further, the construction of these methods is a huge task, which needs a lot of time and manpower; thus, these methods cannot efficiently purify the water bodies.